Probiotics for the mind: How gut bacteria may affect our mental health
- 06.09.2021
- English Articles
- Hanna Huber
- Rieke Sproten
- Marie-Christine Simon
Peer reviewed / Manuscript (original) submitted: 14 May 2020 / Revision accepted: 11 September 2020
Introduction
With up to 1013 bacteria and more than a hundred bacterial species, the gastrointestinal tract contains the largest proportion of the physiological human flora. These bacteria are mainly commensals and usually live in symbiosis with their host. The totality of all microorganisms colonizing the human organism, including their genetic material, is called microbiome. The development of the human microbiome is a complex process that is crucial for the physiology of the organism and begins with birth. The fetal, germ-free intestine is colonized during birth with microorganisms from the birth canal or from the skin of the mother. The microbiome changes continuously during life span. Influencing factors such as genetics, age, gender, geography, stress level and health conditions can affect the diversity and composition of the gut microorganisms [1].
Our understanding of the complexity and diversity of the microbiome is mainly due to the advancement in sequencing technology, which allows detailed analysis of all bacteria and viruses that colonize the human organism [2]. Today, it is known that the intestinal microorganisms play a significant role in the maintenance of a physiological homeostasis as well as in the pathogenesis of various diseases.
Abstract
The human gut with its complex microbial community, the so-called gut microbiota, is also of relevance for the research field of neuroscience. Recent studies have shown that the gut and the microorganisms living in the gut, communicate bidirectionally with the central nervous system and may influence brain functions and behavior. Disorders of this bidirectional communication system, also known as ‘gut-brain axis’, might be involved in the development of neurological and mental disorders. Preclinical and clinical studies indicate that probiotics modulate the gut microbiota and therewith may have a preventive effect on progression of neurological and mental diseases. By elucidating the underlying mechanisms and performing further clinical trials, probiotics may possibly be considered as a new approach for the treatment of mental illnesses such as depression and anxiety disorders.
Keywords: microbiota, gut-brain axis, probiotics, depression, anxiety, mind, “psychobiotics”
